Complete all time attack and body count challenges in an arena.
Turn of Arena AI
To turn off the Arena AI, go to the Title Screen and press these buttons: X,
CIRCLE, CIRCLE, CIRCLE, X, SQUARE, SQUARE, SQUARE, X, CIRCLE, SQUARE, X.

After you win the 1st level, you will be able to visit the Sage. He'll be on
the 2nd level of the inn. Once he's there, you can visit him at any time to
replay levels you've completed, or see "Rewards" you've unlocked along the way.